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Diagnostic Aids

Typical causes for DTC C1102 to set:

Weak or discharged battery
Poor battery terminal contact
Excessive battery draws from factory or after-market equipment parasitic load.
Poor battery ground at block or chassis
Poor terminal contact at the EBCM
Poor EBCM ground connection
Charging system malfunction generator

Thoroughly inspect the wiring and the connectors. Failure to inspect the wiring and the connectors carefully and fully can cause replacement of parts without repairing the malfunction.

DTC C1102

Step	Action	Values	Yes	No
Schematic Reference: ABS Schematics Connector End View Reference: ABS Connector End Views
1	Did you perform the Diagnostic System Check - Vehicle?	-	Go to Step 2	Go to Diagnostic System Check - Vehicle
2	Disconnect the electronic brake control module (EBCM) connector. Turn the ignition switch ON. Check the voltage between terminal 4 and 8 of the EBCM connector. Check the voltage between terminal 4 and 24 of the EBCM connector. Were the voltages within the specified range?	9.4-17 V	Go to Step 3	Go to Step 4
3	Replace the EBCM. Refer to Brake Modulator Assembly Replacement . Did you complete the replacement?	-	Go to Step 12	-
4	Check the battery voltage between the terminal (+) and terminal (-) of the battery. Was the voltage within the specified range?	9.4-17 V	Go to Step 6	Go to Step 5
5	Replace the battery.	-	Go to Step 12	-
6	Check the resistance between terminal 4 of the EBCM connector and the terminal (+) of the battery. Does the resistance measure less than the specified value?	1 Ω	Go to Step 8	Go to Step 7
7	Check both the terminals mentioned in step 6. Repair the terminals, as needed. Check the EBCM connector and wiring harness. Repair or replace the wiring harness as needed. Did you find and correct the condition?	-	Go to Step 12	-
8	Check the resistance between terminal 8, 24 and G104. Does the resistance measure less than the specified value?	1 Ω	Go to Step 10	Go to Step 9
9	Repair or replace the EBCM connector or G104. Did you complete the repair?	-	Go to Step 12	-
10	Connect a voltmeter to the positive and negative terminal of the battery. Turn OFF all accessories. Start the engine. Monitor the voltage on the meter with the engine running at 2,000 RPM for several seconds. And also check the voltage between terminal 4 and 8. And also check the voltage between terminal 4 and 24. Do the voltages measure less than the specified value?	17 V	Go to Step 12	Go to Step 11
11	Repair the alternator. Did you complete the repair?	-	Go to Step 12	-
12	Use the scan tool in order to clear the DTCs. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text. Does the DTC reset?	-	Go to Step 2	System OK